Polymeric material

Abstract

An assembly comprises first and second parts which bear against one another, wherein said first part comprises a polyetherketoneketone and said second part comprises a polyetherketoneketone. The parts bear against one another such that one or both of the parts may have a tendency to wear and/or produce wear debris by virtue of contact between the parts. The materials used, however, minimise wear and the production of such wear debris.

1 . An assembly comprising first and second parts which bear against one another, wherein said first part comprises a polyetherketoneketone. 
   
   
       2 . An assembly according to  claim 1 , wherein said first and second parts bear against one another so that, in use, one or both of the parts may have a tendency to wear and/or produce wear debris by virtue of contact between the parts. 
   
   
       3 . An assembly according to  claim 1 , wherein said second part comprises a polyetherketoneketone. 
   
   
       4 . An assembly according to  claim 1 , wherein a bearing surface of said first part which contacts a bearing surface of said second part consists essentially of a first composition which comprises at least 80 wt % polyetherketoneketone. 
   
   
       5 . An assembly according to  claim 4 , wherein said first composition consists essentially of polyetherketoneketone. 
   
   
       6 . An assembly according to  claim 4 , wherein a or said bearing surface of said second part consists essentially of a second composition which comprises at least 80 wt % polyetherketoneketone. 
   
   
       7 . An assembly according to  claim 6 , wherein said second composition consists essentially of polyetherketoneketone. 
   
   
       8 . An assembly according to  claim 1 , wherein said first part includes at least 0.5 grams of polyetherketoneketone, said second part includes at least 0.5 grams of polyetherketoneketone, said first part includes less than 5 kg of polyetherketoneketone and said second part includes less than 5 kg of polyetherketoneketone. 
   
   
       9 . An assembly according to  claim 1 , wherein said first part and said second part are moveable relative to one another. 
   
   
       10 . An assembly according to  claim 1 , wherein said assembly is for implantation in a human body to replace a structural element of the human body. 
   
   
       11 . An assembly according to  claim 1 , wherein said first part is made substantially entirely from polyetherketoneketone and said second part is made substantially entirely from polyetheretherketone. 
   
   
       12 . An assembly according to  claim 1 , wherein one of said first or second parts of said assembly may define a head and the other part may define a socket within which the head is pivotable. 
   
   
       13 . An assembly according to  claim 1 , wherein said first part and said second part comprise the same material. 
   
   
       14 . A kit for providing an assembly according to  claim 1 , the kit comprising:
 (a) a first part as described according to  claim 1 ;   (b) a second part as described according to  claim 1 ;   
     wherein said first part and said second part are cooperable to define an assembly wherein said first and second parts bear against one another. 
   
   
       15 . A package, which comprises an assembly or kit according to  claim 1 . 
   
   
       16 . A method of manufacturing a first part according to  claim 1 , the method comprising forming a bearing surface of said first part from a polyetherketoneketone. 
   
   
       17 . A method of making an assembly according to  claim 1 , the method comprising:
 (a) selecting a first part as described according to  claim 1 ;   (b) selecting a second part as described according to  claim 1 ; and   (c) contacting the first and second parts so that the parts bear against one another and define said assembly.   
   
   
       18 . The use of a first part as described according to  claim 1 , and a second part as described according to  claim 1  in the manufacture of an assembly which comprises said first and second parts bearing against one another for implantation into the human body.